bug#3782: 23.1.50; Indent works inconsistently in python-mode

Scenario A:
1.  Define a new function:

def foo(bar):

2.  Press tab to indent (this works):
3.  Write an 'if' statement:

def foo(bar):
    if bar:
4.  Press Return.
5.  Press Tab, you will get "Sole indentation." and Emacs does not indent.

Scenario B:
1.  Open a Python source file with functions in it.
2.  Press Return at the end of an exist 'def'.
3.  Pressing Tab may or may not indent.


In GNU Emacs 23.1.50.1 (i686-pc-linux-gnu, GTK+ Version 2.10.11)
 of 2009-07-05 on dagda
Windowing system distributor `The X.Org Foundation', version 11.0.70200000
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Python

Minor modes in effect:
  shell-dirtrack-mode: t
  tooltip-mode: t
  tool-bar-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
t h i n g <return> <backspace> ( ) : <return> <tab> 
i f SPC p l a t g f o r m <backspace> <backspace> <backspace> 
<backspace> <backspace> f o r m . o s - <backspace> 
. a n <backspace> <backspace> n a m e SPC = = SPC ' 
p o s i x ' : <return> <tab> <tab> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> s o m e t h i n 
g . s e <backspace> o m e t h i n g SPC <backspace> 
. s o m e t h i n g SPC = = SPC ' p o x i <backspace> 
<backspace> i x <backspace> <backspace> s i x ' : <return> 
<tab> <tab> <tab> <tab> <tab> <tab> <tab> <tab> <tab> 
<tab> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
SPC = = SPC ' p o s i x ' : <return> <tab> <tab> <tab> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> s o m e t h i n 
g : <return> <tab> <tab> <tab> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <down> 
<down> <backspace> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <menu-bar> <help-menu> <se
nd-emacs-bug-report>

Recent messages:
Closes def syslog_level(self, level):
Closes class Level():
Auto-saving...done
Closes else:
Closes def syslog_level(self, level):
Closes class Level():
Sole indentation [7 times]
Auto-saving...done
Sole indentation [15 times]
Auto-saving...done